稻田氮、磷损失与过程监测方法研究进展

Research Advances on Process and Monitoring Methods of Nitrogen and Phosphorus Loss in Paddy Fields

水稻是我国主要的粮食作物之一。水稻生产过程中土壤和肥料中的部分氮磷元素以溶质或颗粒形态通过淋溶、径流迁移至周围水体,造成地下水污染和水体富营养化。稻田土壤中氨挥发产生的氨气和反硝化反应产生的氧化亚氮气体进入大气,加剧了温室效应。笔者围绕稻田氮磷的气体挥发、径流和淋溶3个流失途径介绍了国内外常用的监测方法,并进一步讨论了针对径流和淋溶这2种流失途径的监测指标、监测频率和监测深度等问题,总结了2种流失途径的主要氮磷流失形态,根据产流特征和施肥时间确定监测时间节点,综合考虑植物吸收和地下水深度确定淋溶监测深度,以期为稻田氮磷流失监测提供相关技术支持和科学依据。

Rice is one of the major cereal crops in China. During the rice production process, part of the nitrogen and phosphorus in the soil and fertilizer migrates to the surrounding water body through leaching and runoff in the fonn of solutes or particles, causing groundwater pollution and eutrophication of water bodies. Ammonia produced by ammonium volatilization in paddy soil and nitric oxide produced by denitrification reactions enter the atmosphere, aggravating the greenhouse effect. The commonly used monitoring methods of gas volatilization, runoff, and leaching in paddy fields from domestic and international studies are introduced, and the monitoring indicators, monitoring frequency, and monitoring depth in the pathways are further discussed; the main nitrogen and phosphorus forms in runoff loss and leaching loss are summarized; the monitoring frequency is detennined by the characteristics of runoff and the tertilization; plant absorption and depth of groundwater should be considered to detennine the depth of leaching monitoring. This study provides a reference for futher monitoring of nitrogen and phosphorus losses in paddy fields.